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You forget that artists and chemists and alchemists were obsessed with these types of issues for since antiquity:

“The notion that light can affect various substances - for instance the suntanning of skin or fading of textile - must have been around since very early times. Ideas of fixing the image seen in mirrors or other ways of creating images automatically may also have been in people’s mind long before anything like photography was developed.

However, there seem to be no historical records of any ideas even remotely resembling photography before 1725, despite early knowledge of light-sensitive materials and the camera obscura.

It has been suggested that some lost type of photographic technology must have been applied before 1357: the Shroud of Turin contains an image that resembles a sepia photographic negative and is much clearer when it is converted to a positive image. The actual method that resulted in this image has not yet been conclusively identified. It first appeared in historical records in 1357 and radiocarbon dating tests indicate it was probably made between 1260 and 1390. No other examples of detailed negative images from before the 19th century are known.

Albertus Magnus (1193/1206–80) discovered silver nitrate and noted that it could blacken skin. Silver nitrate would later be used as a light sensitive material in the photographic emulsion on photographic glass plates and film.

Georg Fabricius (1516–71) discovered silver chloride, later used to make photographic paper...

In 1614 Angelo Sala wrote in his paper Septem Planetarum terrestrium Spagirica recensio: “When you expose powdered silver nitrate to sunlight, it turns black as ink”. He also noted that paper wrapped around silver nitrate for a year had turned black....

Wilhelm Homberg described how light darkened some chemicals (photochemical effect) in 1694...”